There is currently a desire to ensure the sorting of mailings, such as mail items or packages, according to as many sorting directions as possible automatically and with a high throughput. In this respect an installation with a track of receptacles is known, said receptacles being assigned respectively to a sorting direction and with the mailings being allocated to and deposited in said receptacles.
FIG. 1 shows such an installation (see also DE 103 05 847 B3), which allows the sorting of incoming objects or mailings G1, G2 by means of loading facilities or feeders F1, F2. The number and output of the feeders F1, F2 hereby determines a maximum throughput of mailings to be sorted. The mailings G1, G2 are deposited in circulating bags or cassettes A1, A2, . . . , AX of a first track LA by means of the (laterally) arranged appropriate feeders F1, F2. The sorting direction of a mailing is hereby already known. The mailing is transported in its bag along the track LA, until the bag is located in front of an empty storage compartment S1, S2, . . . , SX, into which the mailing is passed. This storage compartment hereby operates as a buffer S between the first track LA and a second track LB, which has circulating receptacles B1, B2, . . . , B5, C1, C2. The mailings from the buffer S are allocated according to the sorting directions by transferring the mailings to the various receptacles, when a corresponding receptacle circulates in front of the required storage compartment of the buffer S. Each of said receptacles is assigned a sorting direction, which designates for example a predominant sorting direction, for a large city perhaps, or a further remaining sorting direction, for smaller districts for example. The large number/volume of mailings for predominant sorting directions compared with mailings with remaining sorting directions means that in practice a further larger plurality n (n=2, 3, 4, . . . ) of receptacles B1, B2, . . . , B5 is used for predominantly preselected sorting directions in track LB and a smaller second number m (m−1, 2, 3, . . . and m<n) of further receptacles C1, C2 is used for the remaining sorting directions. Therefore all mailings from the buffer S are individually allocated to or deposited in the receptacles B1, B2, . . . , B5 of the second track LB according to the first preselected sorting directions but the remaining mailings are not sorted individually but are for example stacked according to the second remaining sorting directions due to the limited number of receptacles C1, C2 still available in the second track LB.
Therefore in this first step the mailings with predominant sorting directions are sorted completely while the further mailings with remaining sorting directions are deposited in one or a few receptacles, without being sorted individually. The remaining mailings therefore still have to undergo a more refined sorting process, for example by then being fed back into the feeders F1, F2 with more refined setting of the assigned sorting directions at the two tracks LA, LB and at the buffer S. This further refined sorting operation can take place at a specific time, for example after the mailings with predominant sorting directions have already been sorted. This process is generally carried out manually, when an operator of the installation determines that the number of incoming mailings with predominant sorting directions is decreasing. If this is not the case, because a new load of mailings with predominant sorting directions comes in, these mailings must be sorted later. In other words the installation can generally only sort overall as a maximum with half the throughput for example.